Bank Swallow - Riparia riparia
Bank Swallow - Riparia riparia
General Description
Small swallow; length 12 cm, mass 10.2-18.8 g. Sexes similar in appearance, and plumage similar throughout year. Adult has grayish-brown mantle, rump, and wing-coverts, contrasting with darker brown remiges and rectrices. Throat white, contrasting with distinct brown breast-band and grayish-brown crown. Brown breast band can extend to belly as sharp spike. This species is a highly social land bird. It nests in colonies ranging from 10 to almost 2000 active nests. In the Old World, is known as the Sand Martin. (Garrison, Barrett A., The Birds of North America, No. 414, 1999).
Distribution
Montana Range
Migration
In the Bozeman area, normal migration periods are May 7 to 25 and August 15 to September 10.
Habitat
Presently breeds primarily in lowland areas along ocean coasts, rivers, streams, lakes, reservoirs, and wetlands. Nesting colonies also found in artificial sites such as sand and gravel quarries and road cuts. Most rivers and streams with nesting habitats are low-gradient, meandering waterways with eroding streamside banks (Garrison 1999).
Food Habits
Takes flying or jumping insects almost exclusively on the wing. Occasionally eats terrestrial and aquatic insects or larvae. Rare consumption of vegetable matter appears to be accidental (Garrison 1999).
Reproductive Characteristics
Nests in erodible soils on vertical or near-vertical banks and bluffs in lowland areas. Many colonies are found in sand and gravel quarries. Individuals choose colony site first, then burrow site. Eggs are subelliptical in shape, white in color. Clutch size ranges 1 to 9 throughout breeding range. (Garrison 1999). Near Fortine, egg dates are June 12 to July 6. Statewide, nests are seen in June and July, with young out of the nest in early August.